1. Field of the Disclosure
The present disclosure relates to a client device, and more specifically, relates to augmented reality technology that overlays virtual information onto information given by perceptions from a real-world environment.
2. Description of Related Art
In recent years, attention has been focusing on augmented reality technology, in which computer-generated virtual information (virtual objects) are overlaid onto information given by perceptions from a real-world environment. In order to superimpose a virtual object over the real world, it is necessary to align the position and orientation of the camera capturing the virtual object (the virtual camera) with the position and orientation of the camera capturing the real world. Acquisition of the position and orientation of the camera capturing the real world is possible by a technique such as calculation from image information regarding a marker image appearing in a captured image captured by a camera.
For the marker image, an image with a known shape, design, or other feature is prepared in advance. The marker image is placed at a given position over a real-world space, and the marker image is recognized by a camera. Then, the position and orientation of the camera in the real-world coordinate system, being a coordinate system for the real world, is back-calculated from the position and shape of the marker image contained in an image being captured by the camera. Once information on the position and orientation of the camera in the real-world coordinate system is obtained, that information can be used to generate a virtual object, and the generated virtual object can be superimposed over a captured image.
If position information and orientation information is mutually shared among users in a virtual space provided by such augmented reality, virtual information according to each person's position and orientation can be displayed. For example, Japanese Unexamined Patent Application Publication No. 2011-107893 describes technology configured such that a virtual space can be shared with other client devices by ascertaining position information regarding the other client devices.
However, with the technology described in Japanese Unexamined Patent Application Publication No. 2011-107893, position information regarding other client devices is acquired on the basis of shape information and the positions of other client devices included in a captured image from a camera. For this reason, sharing the same virtual space among a plurality of users requires that other client devices wanting to share the virtual space must be inside that space.